Heat riser valve ?

[MAC71]

Is the heat riser valve in the open or closed position?

[seattle gmc]

looks like its in the closed position.

[MAC71]

Originally Posted by seattle gmc

looks like its in the closed position.

I thought it was closed. It moves freely but will not move to the other position even after a long highway drive. I just wired it to the other position and will see how it runs on the way to work in the morning.

[Userone]

I'm pretty sure the exhaust gas opens it when it flows shouldn't matter what temp its at

[i82much]

Originally Posted by Userone

I'm pretty sure the exhaust gas opens it when it flows shouldn't matter what temp its at

That is how mine works. When the truck is cold and you blip the throttle, it barely moves. When the truck is warmed up and you blip the throttle, it moves a lot more. I don't think it just opens up because it is hot. I think the bimetallic coil provides varying amounts of resistance against the exhaust depending on the temp, but unless you are giving it some throttle there isn't enough exhaust pressure to open it all the way even when it is fully warmed up.

[seattle gmc]

I just replaced mine. The only time it seems to open up is when i push lever down. Maybe it is moving when the throttle is aplied, i don't know?